Fig. 12.

Diagram of the different modes of fin/limb muscle formation. (A) Amniotes and anurans use long-range migration of individual mesenchymal migratory myoblasts in both the fore- and hindlimbs for limb muscle formation. Bony fish deploy this mode of fin muscle formation in the pectoral fins. (B) Zebrafish utilise the long-range migration of individual mesenchymal migratory myoblasts from an epithelial myotomal extension to make the muscle of the pelvic fin. (C) Chondrichthyans utilise the primitive mechanism of direct epithelial extension to generate the muscle of pectoral and pelvic fins (figure reproduced from Cole et al. 2011).